Apparatus for concentrating solutions by freezing.



E. MONTI.

APPARATUS FOR OONGENTRATING SOLUTIONS BY FREEZING.

APPLICATION FILED MAR.20, 1907. 925,820. Patented June 22. 1909.

6 SHEETS-SHEET 1.

E. MONTI.

APPARATUS FOR OONGENTRATING SOLUTIONS BY FREEZING.

APPLIOATION FILED MAR. 20. 1907.

6 SHEETS-SHEET 2.

........... Fig. 2

Patented June 22, 1909.

E. MONTI.

APPARATUS FOR GONCBNTRATING SOLUTIONS BY FREEZING.

' APPLICATION IILED MAR. 20. 1907. 925,820. Patented June 22, 1909.

6 SHEETS-SHEET 3.

E. MONTI.

APPARATUS FOR CONCENTRATING SOLUTIONS BY FREEZING.

APPLIOATION FILED MAR. 20, 1907.

Patented June 22, 1909.

6 SHEETS-SHEET 4.

B. MONTI. APPARATUS FOR GONQENTRATING SOLUTIONS BY FREEZING.

APPLIGATION FILED MAR. 20, 1907. 925,820. Patented June 22, 1909.

6 SHEETS-SHEET 6.

m9 m m? E mm @TMWQ wq fimwu 3&5

E. MONTI.

APPARATUS FOR OONOENTRATING SOLUTIONS BY FREEZING.

APPLICATION FILED MAR. 20. 1907.

Patented June 22, 1909.

6 SHEETS-SHEET 6.

EUDO MONTI, OF TURIN, ITALY.

APPARATUS FOR CONCENTRATING SOLUTIONS BY FREEZING.

Specification of Letters Patent.

Patented June 22, 1909.

Application filed larch 20, 1907. Serial no. 363,527.

To all whom it may concern: i Be it known that I, EUDo MONTI, a subject of the King of Italy, and'resident of Turin, Italy, have invented certain new and useful improvements in apparatus for concentrating solutions by freezing and systematically displacing the soluble substances from the ice crystals, of which the following is a specification.

The present invention relates to improvements in the apparatus for carrying on the process of concentrating solutions by freezing protected by my American Patent No. 761387 dated May 31st 1904 and patent ap plications Ser. Nos. 223919, 223920 filed September 9th 1904, Ser. No. 285936 filed November 4th 1905, and especially of the apparatus in which the freezing of the solution to be concentrated is operated by means of cooled brine, which is caused to circulate in pipes plunged in the solution to be concentrated.

These improvements consist in the eculiar construction of the freezing tanks to e used for the concentration of largequantities of liquids, which tanks being square may be constructed of a very large size using armored or reinforced concrete, wood or any other suitable material.

These improvements consist further in the use of straight steel or other suitable pipes varnished or coated with tar, by means of which a large interchanging surface may be obtained much cheaper than by using the usual coils.

Another aim of the present invention is to provide an apparatus, by which it is possible to efi'cct readily and evenly, while the dislaceinent is going on, a spraying of the rozcn mass with the more and more diluted displacing solutions obtained in a former operation and to cause the displacement to take place eventually in an atmosphereof an inert gas heavier than the air.

The present improvements consist further in reducing the number of cocks, that may be substituted with sliding valves or partitions and inthe eneral arran ement of the a paratus in suc 1 a way as to full utilize the ieat absorbed by the melting oft e ice, separated in previous operations, for the further cooling of the gas already liquefied coming from the condenser.

These improvements relate further to a special arrangement of the apparatus, by which the brine is caused to circulate alter nately in the freezing pipes at the ordinary temperature for the urpose of melting .the layer of hard ice whic often adheres to said tubes. Another aim is to provide an arrangement whereby to utilize the heat absorbed by the Y lukewarm brine circulating in the freezing pipes for the further cooling of the liquefied gas or of the solution to be frozen; thus allowing the use of the same uantity of brine for softening the impcrmcaile ice adhering'to' the tubes, in an unlimited number of opera tions, the result being to considerably di. minish both the cost of the plant and the runningexpenses.

'In the annexed constructional forms of the a paratus and a complete plant of a battery 0 freezing tanks.

Figure 1 is a sectional longitudinal View of-a freezing tank. Fig. 2, on the'left half, is

a vertical cross section of said freezing tank on line a-. a of Fig. 1 and, on the right half, an end view of; said freezing tank with the refri erator of the ice machine.

Fig. 3 is a combination view on an enlarged scale, comprising, on the left half, the ver-' tical cross section of then per part of said tank on line b. b of Fig. 1 and, on the gight half, a similar section on line -c. c of 1 1. se tion, a detail of the top-compartments of a tank, in which terminate the tubes in which the cooled brine circulates; Figs. 5 and 6 are respectively a side view and a cross section of the armor plates used in connection with the partitions in the top compartments of the tank. Fig. 7 is an end view of a ortion of the tube holders in the tanks. 3. 8 is a plan view of same and Fig. 9 an end and side view of one of said holders. 10 is a longitudinal section of a modified form of a freezing tank. Fig. 11 is a front view'cf the traveling crane and of the spraying reservoir cross section of same on lino' e. e of Fig. 14. Fig. 16 is an end viewot same. Fig. 17 is a dia rammatic plan View of a series of four reezing tanks alternately cooled by a single ice machine.

The freezing tank --1 (Fig. 1) may be drawings are shown some i i Fig. 4 shows in vertical longitudinai besides the outer walls 2-, with two inner generally made of'steel varnished or coated i lect'or com artment '5 on the left'side.

Through built of reinforced concrete, wood or other i suitable material and is provided at its ends,

walls -3. 4 forming thus at each end of the tank -1-, the two compartments 5. .6. Straight metallic tubes 7.'8

with tar, but which may of course be made i of any other material to suit the characters of the solution to be concentrated, are arranged longitudinally in the tank -1-;- in as many horizontal ranges as accords to the height of the tank or basin. The ranges of the tubes .7 go from the left feeding compartment 6 (Fig. 1) to the right col-lecting compartment -5 and vice versa the ranges of the tubes '''S-' g o from the feeding compartment -.6 on the right to the col- Moreover-t ie series of pipes 8 and 7 are disposed in quincunx .as shown at Fig. 2. ipes 7 and 8 flows in opposite irections the cool brine coming from the refrigerator 15 of the ice machine and passing through the pipes -9' valves '10 and pipes 11, these latter crossing the walls 2. 3- and ending in'the compartments '6-. It is obvious that' said brine will then pass from the left feed ing compartment 6'- through pipes -'7 to the collector -5 on the right'side and from the right feedin g' compartment 6 through pipes 8'- to the collector 5 on the left side. In this way all the brine reaches the collectors 5- passing'through freezing pipes 7- and 8 is discharged by the tubes 12 and goes again through valve -l.3 and tubes l4 to the refrigerator -l5 of the freezing machine. This circulation is obtained by means of the pumps 25 (only ncis visible in Fig. 2) inserted on the tubes 14* and will cause the level of the brin'elin thecompartment 5 to sink; it follows that the circulation of the brine is controlled by the pumps 25 and may be stopped or slackened by stopping or reducing the speed of said pu inps. Owing to the uniform arrangement of the tubes 7 8--' and moreover to th e fact that the flow of cooled brine in the pipes 7. 8 has an inverted direction, an even cooling and therefore an even freezing of the solution to be concentrated is obtained.

A sim ler arrangement of the freezing tubes is s 10WI1 in Fig. '10, which same gives useful results provided that the circulation of the brine in the tubes be 'very quick. This condition involves a greater use of energy, which is however compensated by a cheaper instalment. In this constructional form there is a single feeding compartment 6 on the right side fed by the admission tube "11-. from said compartment 6- the cooled brine passes through the tubes ---7 into the discharging compartment-1 5., from which it is discharged through the outlet tube .12. SlIIl ler form of construction the direction of the rine circulation in all the freezing pipesis the same and in order to obtain an even congelation it is necessary that the temperature of the feeding and waste brine be but slight-ly-i'liiferent. An even congelation of the solution may of course be obtained also by causing the refrigerated brine to circulatev in turns in opposite directions through pipes 7. This mode of operation maybe obtained in the embodiment shown in Fig. 10 by connecting the feeding and collecting compartment alternately with the brine pump by means of flexible pipes and opening or shutting accordingly the cooks or partitions controlling. the overflow pi es of said compartments or in any other suitable way.

The pipes '1 1 (Figs. 1 2) may be caused to communicate with the I ipes 26 by openingthe valves 27. roni said pipes comes the lukewarm brine, which may thus be drawn in the pi es 7 and 8 instead of.

the cooled brine w en the circulation of this latter has been stopped by closing the valves 10,' and the feeding and waste reservoirs 6 and 5 emptied for the pur pose hereinafter explained. In the same manner the outlet pipes -12 may be connected, by opening the valves 28-, with the pipes 21 leading the brine into the tanks 22., from which by means of the tubes -23 and pumps 24, it may be sent to an interchanger or condenser or. anywhere else, in the way and for the purpose hereafter set forth.

The circulation of the cooled brine in the different ranges of tubes may be controlled by means of the sliding partition 16 running along the surface of the walls -43- of the feeding compartment 5. The

sliding partitions 16 are suspended by means of chains -17' to the winch drums 18* operated by the cranks 19 and slide in the vertical grooves 2(l running along the walls 3-. Consequently, by lowering the partitions -1 6, the circulation Evidently in this.

stop, thus hindering the cooling of the corresponding layers of solution. It is however easy when the solution to be concentrated is heavier than the water to control thefreezing of the different layers of solution in the tank in such a way as to enrich the lower layers'before freezing them, as it has been described and claimed in my U. S. patent application No. 285. 36.

The Figs. 3, 4 5, (i show on an enlarged scale the details of construction of the walls 3. 4 supporting the pi 0 heads. The wall 3, which is crossed y one half only of the pipes 7. 8 is made of wooden planks cast iron or properly shcped brick-or being placed; so t concrete, cement, tar or asphalt is then poured between the plates and hardening there, forms a. water tight closure. The wall -4 is constructed in the same wa but the side plates -64 (Fig; 6) are castin such a way as to allow both ranges of *ipes' to pass through; said plates are there ore' provided with a, double number of notches 62- for the tubes -7 and -'65'for the tubes 8 they are also provided withpins -63- for securing them to the concrete or tar mass constituting the wall 4.

In order to support the freezing pipes 7. 8"i'nside the tank -1, thus preventing any alteration in the res ective distance which would affect the un formity of the freezing, I employ the detachable holders shown in front view in Fig. 7 and in plan view in Fig. 8, while F ig. 9 shows, in front and side view, e. separated element -66 of said holders, which need no further description' inasmuch as they are not of my invention and might, evidently be substituted by any other suitable form allowinga quick removal of the pipes when repairs are necessary.

When the freezing in tank 1 is completed, the dis )lacement is carried on, as described in my S. Patent No. 761387 dated .\lay 31st 1904; that is to say by spraying the frozen mass with more and more diluted solutions obtained in previous operations. In order to obtain an even spraying of the frozen mess, Lemploy the spraying apparatus shown in Figs. 11, 12, 13. Said apparatus is supported by means of chains 3() by an overhead traveling crane --3'1 operated by means of an electric motor or in any other suitable way, sliding on beams -;32- supported by the pillars ;33 arranged on the sidewalls 3-t of the tank I (Figs. 1, 2). 'The lower part -Zi5 of the tank 2!) is cylindrical and provided with holes 36. p A sliding plate fitting exactly on the inner surface of the bottom '35, is supported by the shaft 3R crossing the reservoirs walls .3S) by means of water tightbearings and is worked from the outside by means of the crank ---39. It appears clearly from l 'ig. l2; 'tha t by suitably turning the sliding stoppcr -11? by means of the il s) ll is lins'sililt; (llllil' lo sllull completely the holes 36-. or to leave open more or less of them, thus enabling the operator to regulate the quantity of solution dripping from the reservoir 29-. This latter is provided with an air tight cover 40 secured thereto by means of the bolts .--tl, the same being applied when it is desi-red to sprinkle the dis lacing solution under gas pressure. Suit cover is provided with an inlet 42, a cock 43 and a manometer 44. In order to effect in this case the sprinkling under pressure of dry carbonic acid or any other suitable gas, after having filled the reservoir 29 with the solutiono1-)era tion which may also be effected under )ressure of dry carbonic ncid-,

- I connect coc 43 with the outlet tube of a cylinder containing the compressed dry carbonic acid; in this way I cause the liquid contained in 29 to sprinkle-(nit in a finelv and evenly divided shower The quantity of s irinkled 'liq'uid isevid'ently proportioned to t e pressure in 29 and to the number and diameter of the openings 36- left free by the stopper 3'7. By moving the sprinkler 2'6 to-andfro above the frozen mass contained in the tank -1 by means of the traveling crane 31, the. underlying mass of ice crystals will he s )rinkled evenly thus insuring a com ilete and even displacement of the weak solutions. When it is desired to effect the dis )lacement out of contact with the air, the frozen solution ma y be covered with a'laycr of dry carbonic acid or other inert or reducing, gas heavier than the air. which is easily held by the walls of the tank 1: the same being for said purpose raised above the level of the frozen mass. The sprinkling reservoir -29- is then lowered enough to be plunged into the layer of inert gas, thus effecting the displacement out of contact with the air.

A modified form of the spraying apparatus isillustrated in Figs. l4, 15, 16. For varying the quantity of liquid coming out of the reservoir. I employ here instead of the stopper 37 and cylindricalbored bottom 35, valves 67 controlling the liquid admission in the short sleeves -68 connecting the reservoir 29 with the perforated tube --6.)--. The valves 6T are pro vided with stems Tt) secured to the clip T.'l--- of eccentrics 72 mounted on the shaft -T3- coming out of the reservoir -2Sl and controlled bv means of cranks It is evident that by turning the shaft 73, the valves 67 areraiscd more or less or fully closed on their seats arranged at the top of the sleeves -6S---: so that in the position of the crank 3Si shown in full lines in Fig. 16, the valves are quite closed. in the position .-li()\\'ll in dotted lines, they are wide opened. it is thus pos sible to control the quantity of liquid coming out of the reservoir ---;2L ---v It is obvious that any other form of sprinkling apparatus may beemployed provided it. suits the purpose of spraying the liquid evenly on the surface of the frozen mass. 7

The solutions drawn from the frozen mass by the displacing process are collected at the bottom of the tank -1, which slopes to--. ward the tube .45- in which llow suc-,

1 ice containedin thetank with a quantity of cessively the concentrated solutions and the diluted solutions dripping afterward-from;

the frozen mass and astly the watcrof the melting ice left in the tank. The concentrating plant 17 will now be described. four freezing tanks -1 l 1, 1 ]5 illustrated in-Fig.

is the refrigerator-of the ice machine. con.

nected with one, or more of the three. condensers +48. 49.. 50-, which maybe 6H1- ployed together or separately, by connecting The condensation of the compressed gas is obtained by the circulation of cooling water in the condenser them in tandem series.

48 in condenser or rather interchanger 47, water at 0;wluch has been used for melting the ice in the freezing tanks is caused to circulate and in v50- the liquefied gas may be, cooled by inverted circulation of brine, which hasbeen used to soften the hard ice coatingthe freezing pip es. The liquefied and cooled gas coming from the-condenseror interchangers arrives through the tube 51- at the expansion valve and goes from thence to the evaporator and through the suction pipe -54 back to the compressor The cooledbrine is drawn from the refrigerator 15--,. through the piping ;9 and valves 10 into the; feeding compart ments- 6- of said tanks, passes through the freezing pipes 7e; and 8-- into the collectors -5- and through waste pipe --12 and valve -13- into return pipe 1-t which conveysit back to the refrigerator 15';- The brine circulation is controlled by the difference of level between the feeding and waste reservoirs caused by the action of pumps, connected in circuit with pipe -14 It is obvious that by turning the cocks or valves 10,123 it is possible to put one or more of the tanks out of circuit. In the same way each tank of the series may be put in communication with the collecting reservoirs 22 by means of the cooks 28- and tubes 21-. Brine from the reservoir at a relatively high tem erature, may. be caused to circulate throng ithe freezing pipes 7, and.8 of each; tank, by closing cocks 10 andv opening cocks 27. The

concentrated solutions drawn from the tanks 1- to 1 during the. displacement.

and which are discharged by the tubes-t5 45 are led to one or more suitable reservoirs not shown in the drawing. The more, and more diluted solutions are afterward :conveyed into the barrels ---56-'-, from which The same includes 1 after the displacement is over.

they may be drawn by means of the pump 57 in order to use them to displace the concentrated solution from the ice crystals in a following operation. 7

--5S-- is thereservoir for the icy water obtained by melting the ice left in the tanks The melting of the ice must be operated by spraying the ,ing process in one of said tanks is carried on so slowly as to allow tl'ie'operator time to draw the concentrated solution, to soften the hard ice coating the freezing pipes, to operate the .lis )lace1nent, the melting of the separated and depurated ice and to fill the tank with a new quantity of solution to be concentrated while the freezing in the other tank is going -on..

The following demonstration shows that by means of the above described set of appa ratus, the process of concentration may be carried on in a continuous way. In fact while the freezing is going on in tank 1, the concentrated solutionis caused to drip. from the ice crystals filling the tank 1 and contemporaneously I operate the displacement in tank '1, while I pour cooling water on tank 1,, in order to melt the ice leftafter the displacement is over. I draw the refrigerated water into the well 58 and fill again said tank 1" with a new charge of solution tobe frozen after the freezing in tank 1 u is completed. Being assumed that tank 1* is being frozen,

tank -1" has already beenfrozen and the concentrated solution is dripping from the ice, in tank 1" the dis lacelnent isgoing on, in tank --1 the c ear ice has been melted by a suitable quantity of cooling a? ter, the water has been drawn and the tan is ready to be filled with a new charge of-sollr-f tion. After the tank ?-1 has be'en-fill'e'dHZO with a new charge solution, the cocks 10, 13 must. be opened so that thecooled brine coming from the refrigerator 15 of the icemachine be allowed to circulate in the tubes-7, 8- of the said tank.

The ta nk--*" 1 in which the freezing is achieverhflthe solution having been cooled to a temperature corresponding to the desired concentration, is cut out ,of the cold brine circulation by closing the cocks 13- 130 and as the. cooling pipes and the feeding and F -'-6- still cont ain a considerable quantity of cooled brine. which prevent the melting of the ice sticking 3 3 l I add the necessary cuantity of cooling water at the lowest possil to the freezing pi ies, I operate as follows: 1. 1 open the discharging pipe -45"- and allow the portion of concentrated solution not held by capillarity to drip. I discharge then from the freezing pipes 7. S and from the compartments -5.6-- the cold brine by opening the cocks 2S- corresponding to said tank .l"-. Said brine )asses into the reservoir *-'22", from which by means of the pumps '24-- and through the tubes 23 returns through the tubes 14 to the refrigerator of the machine. hen the cold brine filling the tubes and the compartments of the tank -1"- has been drawn, the cocks 27 are opened: thus the solution at the ordinary temperature coming from the cistern 55-- through the tubes 26 passes into the battery of tubes of the tank 1" and reaches cooled the tanks 22 from which it may be. conveyed into the interchangers 48. 49. T he flow of a certain uantity of comparatively warm brine in t to freezing pipes of -1 is necessary before starting the displacement in order to soften the layer of compact ice adhering to the freezing pipes formed while the concentrated solution is dripping from the ice, this layer being almost impermeable would hinder the displacement of the interposed soluble matters. By the flowing of this solution at the outer temperature, I obtain both the advantage of facilitating the further dis lacement and of making useof the heat absor )ed by the melting of the com act ice coating the freezing pipes 7. 8 o the tanks 1" in order to cool said brine from the original temperature to about 0 (7., the brine thus cooled being used to cool other liquid or gases in an interchanger or in the condenser. After the layer of compact ice coating the tubes 7. 8 of -b appears to be softened the displacement is carried on as described in my prior patents, by pumping the displacing solutions from the reservoirs -56 by means of the pump 57 and conveying them into the reservoir 29 suspended at the overhead traveling crane. Owmg to the form of said reservoir --29 and the to-and-fro'motion imparted by the traveling crane as above described, it is possible to obtain an even spraying of the frozen mass and therefore an even and complete displacement. The conccntrated solutions thus obtained and flowing from the cocks 45 are conveyed to suitable reservoirs not shown in the drawings, while the more and more diluted solutions are conveyed to the reservoirs -56 to serve as displacing solutions in a subsequent operation. After these operations are over, there remain in the tank -1 a mass of nearly pure ice. 'lhis tank is exactly in the condition in which it has been assumed the tank ---l-- was and-is therefore readv for starting a new operation. In order to melt the ice contained in the tank ile temperature in order to obtain the greatest quantity of water cooled to about 0 (7., which is col lected in the well -5S, from which it will be drawn at the proper time in order to be caused to circulate either in the condenser -49 or in the interchange! 59. 60-. The tank --1, from which the icy melting water has already been drawn is ready to be filled with the solution to beconcentrated. This solution before being admitted into 1 may be caused to circulate through the intcrchangers 59.'60 in countercurrent with the cold water at 0 C drawn from the cistern -5S-. In this way the temperature of this solution is lowered before pouring it into the tank l When the tank 1 is filled, it is inserted into the circuit by opening the cocks 1(). 13.

Claims.

1. In an apparatus fol-concentrating solutions by freezing and separating the soluble matters from the ice crystals, a freezing tank provided with straight tubes arranged longitudinally in the tank in horizontal ranges, and ada ted to convey cooling brine through said tan s in opposite directions; means for regulating the circulation of the brine through said tubes; means for introducing brine of the same temperature as the outside air, into said pipes; and means for displacing the soluble matters from the ice crystals bctween and around said pipes.

2. In an apparatus for concentrating solutions, the combination with the freezing tank; of means for introducing a displacing fluid thereinto, said means comprlsing a s n'inklin reservoir adapted to s ray the disp lacing fIuid evenly over the rozen mass within the freezing tank; a traveling crane for movably mounting said reservoir above the tank; means for raising and lowering the reservoir; and means for moving the reservoir from one end to the other of said freezing tank.

3. In an apparatus of the character described, freezing tanks provided'with distributing and collecting reservoirs'placed at each end of the tanks, said reservoirs being separated one from the other and from the freezing tank by water-tight partitions; a plurality of freezing tubes arranged in horizontal ranges and passing through said part itions in such manner as to form alternate connections between the left feeding coinpartment and the right waste compartment, and between the right feeding reservoir and the left waste reservoir at the other end of the tank; inlet pipes for said feeding conipartments: outlet pipes for said wa te conipartments valves for controlling the flow in said inlet and outlet pipes; reservoirs-for brine adapted to be successively connected with said inlet pipes; and means for returning the brine from the waste reservoirs to either of said brine reservoirs.

4. In an apparatus of the character described, a freezing tank provided with feeding and waste compartments separated from the main freezing chamber by water-tight walls com rising separable plates provided with notclles; and longitudinal pipes arranged in ranges within said freezing chamber and supported by said notched plates.

5. In an apparatus of the character de-- scribed, the combination with the freezing chamber, and feeding and waste compartments on each end thereof; of a plurality of separable elements adapted to be supported by ipes below and to support pipes above, said elements being .provi whereby they are adapted to form a watertight wall about the pipes.

6. In an a paratus of the character described, whic comprises a freezing tank; means for spraying. a frozen solution with a displacing solution, said means comprising an overhead traveling crane mounted upon said tank and adapted to travel over its entire length; and a sprayer of the same width ed with notches for lukewarm brine; collecting reservoirs; a

reservoir for melted ice; interchangers for cooling gas or solutions; a plurality of gascooling condensers adapted to be connected in series or in tandem; and a system of valves whereby each of said tanks indepei'idcntly, may be brought into or thrown out of circuit with the other tanks and with various parts of the plant.

The foregoing specification signed at Turin, Kingdom of Italy, this 19th day of February 1907.

EUDO MON'II. Inpresence of VITALI SALVATORE, ANGELO KEGATO. 

